[Diagnosismed-list] possible bug or feature?

Davis, Wade davisjwa at health.missouri.edu
Thu Apr 22 17:38:09 CEST 2010


Thank you for making available your nice R package!

For one of my predictors, I encounter an error when the AUC is exactly 1. (It is a small sample of only 14). As you can see in my code below I get an error  for the marker " IL1b" at time=5.  I understand that no CI would be calculated in this, but the plot is not generated either.
I don't have any problems  with the other marker/time combinations.

Also, have you considered adding an option for Pepe and Cai's empirical likelihood based CI? The attached paper shows it performs the best in most cases, and only bootstrap-based methods do better when AUC>0.95. Just something to think about...

Thanks for your comments and advice on this.

Wade



> aaron<-read.csv(file="F:\\Aaron Ericsson\\aaron.csv")
> print(aaron)
    status            y marker time truth
1        n    4966.5924   Il1b    3    -1
2        n    9883.7209   Il1b    3    -1
3        n   31528.6624   Il1b    3    -1
4        y   25501.6181   Il1b    3     1
5        y  142161.0169   Il1b    3     1
6        y   56346.1538   Il1b    3     1
7        y  671215.8809   Il1b    3     1
8        y  192592.5926   Il1b    3     1
9        y  385267.8571   Il1b    3     1
10       y  269010.0430   Il1b    3     1
11       y   67777.7778   Il1b    3     1
12       y  201988.6364   Il1b    3     1
13       y   91373.8019   Il1b    3     1
14       y  101904.7619   Il1b    3     1
15       n     487.7506  MIP1a    3    -1
16       n    1399.2248  MIP1a    3    -1
17       n    3590.2335  MIP1a    3    -1
18       y    2800.9709  MIP1a    3     1
19       y   26758.4746  MIP1a    3     1
20       y   23038.4615  MIP1a    3     1
21       y  164640.1985  MIP1a    3     1
22       y   29861.1111  MIP1a    3     1
23       y   46473.2143  MIP1a    3     1
24       y   72022.9555  MIP1a    3     1
25       y    3881.4815  MIP1a    3     1
26       y   28503.7879  MIP1a    3     1
27       y   15543.1310  MIP1a    3     1
28       y   11714.2857  MIP1a    3     1
29       n      77.2829 RANTES    3    -1
30       n       0.0000 RANTES    3    -1
31       n    1036.0934 RANTES    3    -1
32       y     851.1327 RANTES    3     1
33       y    3190.6780 RANTES    3     1
34       y    3984.6154 RANTES    3     1
35       y   35980.1489 RANTES    3     1
36       y   10185.1852 RANTES    3     1
37       y    8705.3571 RANTES    3     1
38       y    3902.4390 RANTES    3     1
39       y    4074.0741 RANTES    3     1
40       y    5473.4848 RANTES    3     1
41       y    3000.0000 RANTES    3     1
42       y    4685.7143 RANTES    3     1
43       n   11715.2104   Il1b    1    -1
44       n   60046.1894   Il1b    1    -1
45       n   77088.0361   Il1b    1    -1
46       y   66242.0382   Il1b    1     1
47       y  226551.2266   Il1b    1     1
48       y 1205766.7100   Il1b    1     1
49       y  519553.0726   Il1b    1     1
50       y   90790.8992   Il1b    1     1
51       y  635601.1184   Il1b    1     1
52       y  692076.2287   Il1b    1     1
53       y  122442.2442   Il1b    1     1
54       y  561085.9729   Il1b    1     1
55       y  501930.5019   Il1b    1     1
56       y  848101.2658   Il1b    1     1
57       n    1268.6084  MIP1a    1    -1
58       n   16859.1224  MIP1a    1    -1
59       n   60835.2144  MIP1a    1    -1
60       y    5171.9745  MIP1a    1     1
61       y  734487.7345  MIP1a    1     1
62       y  238532.1101  MIP1a    1     1
63       y   60055.8659  MIP1a    1     1
64       y    3661.9718  MIP1a    1     1
65       y  287045.6664  MIP1a    1     1
66       y  308926.7803  MIP1a    1     1
67       y   11782.1782  MIP1a    1     1
68       y   76923.0769  MIP1a    1     1
69       y  214414.4144  MIP1a    1     1
70       y  379746.8354  MIP1a    1     1
71       n     288.9968 RANTES    1    -1
72       n     923.7875 RANTES    1    -1
73       n   22404.0632 RANTES    1    -1
74       y    1968.1529 RANTES    1     1
75       y   53968.2540 RANTES    1     1
76       y   26430.7558 RANTES    1     1
77       y    5586.5922 RANTES    1     1
78       y     369.4475 RANTES    1     1
79       y   18434.2964 RANTES    1     1
80       y   40621.8656 RANTES    1     1
81       y    1790.4290 RANTES    1     1
82       y    3400.4525 RANTES    1     1
83       y   22535.3925 RANTES    1     1
84       y   15875.5274 RANTES    1     1
85       n   27902.3747   Il1b    5    -1
86       n   10582.0106   Il1b    5    -1
87       n   38611.1111   Il1b    5    -1
88       y  234274.1935   Il1b    5     1
89       y  583682.0084   Il1b    5     1
90       y   42348.7544   Il1b    5     1
91       y  438288.2883   Il1b    5     1
92       y  191954.0230   Il1b    5     1
93       y  456976.7442   Il1b    5     1
94       y  634146.3415   Il1b    5     1
95       y   79090.9091   Il1b    5     1
96       y  160169.4915   Il1b    5     1
97       y  137213.7405   Il1b    5     1
98       y  223870.9677   Il1b    5     1
99       n    1269.9501  MIP1a    5    -1
100      n    1023.8663  MIP1a    5    -1
101      n    3119.2661  MIP1a    5    -1
102      y   19849.4826  MIP1a    5     1
103      y   22765.2174  MIP1a    5     1
104      y    4586.5922  MIP1a    5     1
105      y   34254.4732  MIP1a    5     1
106      y   17162.9779  MIP1a    5     1
107      y   27427.6860  MIP1a    5     1
108      y   72821.7426  MIP1a    5     1
109      y    3624.4541  MIP1a    5     1
110      y    7972.9730  MIP1a    5     1
111      y    7472.3247  MIP1a    5     1
112      y    1603.3654  MIP1a    5     1
113      n     140.8978 RANTES    5    -1
114      n       0.0000 RANTES    5    -1
115      n     324.7706 RANTES    5    -1
116      y     680.1505 RANTES    5     1
117      y    2208.6957 RANTES    5     1
118      y       0.0000 RANTES    5     1
119      y    2775.3479 RANTES    5     1
120      y     547.2837 RANTES    5     1
121      y    1173.5537 RANTES    5     1
122      y    2334.1327 RANTES    5     1
123      y    1213.9738 RANTES    5     1
124      y     417.2973 RANTES    5     1
125      y     492.6199 RANTES    5     1
126      y       0.0000 RANTES    5     1
>
> aaron.df<-data.frame(aaron, "truth"=as.numeric(aaron$status)-1)
>
>
> library(DiagnosisMed)
>
>
> ROC(test=aaron.df[aaron.df$time==5&aaron.df$marker=="Il1b","y"],
+           gold=aaron.df[aaron.df$time==5&aaron.df$marker=="Il1b","truth.1"],
+     CL = 0.95)
Error in `row.names<-.data.frame`(`*tmp*`, value = c("Max. Accuracy",  :
  invalid 'row.names' length
>

J. Wade Davis, PhD
Assistant Professor
187 Galena DC 018.0
University of Missouri
Columbia, MO 65212
Phone: (573) 882-0770
Fax: (573) 884-4196
MU Biostatistics Group<http://som.missouri.edu/Research/BioStat/Default.aspx>

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